Checking which Debian/Ubuntu version maps to each other can be a pain specially when you are following a tutorials on how to setup something of fix a bug. As not all users are going to know the differences between the versions I have posted a list which should help identify if you are looking at the right information. This is also really helpful when building applications for multiple distros so you know which ones it's likely to work with.
| Debian Name | Debian Version | Ubuntu Name | Ubuntu Version |
|---|---|---|---|
| bullseye | 11 | impish | 21.1 |
| bullseye | 11 | hirsute | 21.04 |
| bullseye | 11 | groovy | 20.1 |
| bullseye | 11 | focal | 20.04 |
| buster | 10 | eoan | 19.1 |
| buster | 10 | disco | 19.04 |
| buster | 10 | cosmic | 18.1 |
| buster | 10 | bionic | 18.04 |
| stretch | 9 | artful | 17.1 |
| stretch | 9 | zesty | 17.04 |
| stretch | 9 | yakkety | 16.1 |
| stretch | 9 | xenial | 16.04 |
| jessie | 8 | wily | 15.1 |
| jessie | 8 | vivid | 15.04 |
| jessie | 8 | utopic | 14.1 |
| jessie | 8 | trusty | 14.04 |
| wheezy | 7 | saucy | 13.1 |
| wheezy | 7 | raring | 13.04 |
| wheezy | 7 | quantal | 12.1 |
| wheezy | 7 | precise | 12.04 |
| wheezy | 7 | oneiric | 11.1 |
| squeeze | 6 | natty | 11.04 |
| squeeze | 6 | maverick | 10.1 |
| squeeze | 6 | lucid | 10.04 |